Safety cap for gas tanks



NOV. 29, 1949 w KNQWLTON 2,489,787 I SAFETY CAP FOR GAS TANKS Filed June1, 1948 5 4 3 X if 7 e f0 FIG. I Z7 15 7% INVENTOR, MM,

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Patented Nov. 29, 1949 2,489,787 SAFETY CAP FOR GAS TANKS Eugene W.Knotilton, Buffalo, N. Y. Application June 1, 1948, Serial No. 30,297

3 Claims.

combustible or volatile fluids.

One of its objects is to provide a protective cap of this characterwhich is so designed and constructed as to insure the automatic ventingof the tank should dangerous pressures and temperatures be generatedtherein as well as to permit the normal breathing of the tank.

Another object of the invention is to provide a combined pressure andtemperture governed safety cap which is simple, compact, self-containedand inexpensive in construction, which can be readily dismembered forcleaning or replacement of its parts, and which is positive and reliablein operation.

Other features of the invention reside in the construction andarrangement of parts hereinafter described and particularly pointed outin the appended claims.

In the accompanying drawings:

Figure l is a cross section of the safety cap embodying my invention.Figure 2 is an exploded perspective view, partly in section, of theparts constituting the improved cap.

, Similar characters of reference indicate corresponding partsthroughout the several views.

By way of example, my safety cap has been shown applied to theexternally threaded neckopening I of a tank I I filled with gasoline orlike fluid. In its preferred construction, this cap consists of a bodyl2, substantially circular in plan, having an internally-threaded,annular attaching flange l3 depending from its bottom side fordetachable connection to the neck-opening of the tank. Ears l4 projectfrom diametrically opposite sides of this body to facilitate screwing itto and unscrewing it from the tank. Depending centrally from thecap-body is a collar l5 providing an axial opening l6 and formed in thetop wall of such body in an annular row about this collar are openingsI! which function, under certain conditions, as vents for the escape ofpressures generated in the tank.

Detachably applied to the top side of the capbody I2 and formingtherewith the self-contained cap structure is a cover I 8 which islikewise substantially circular in plan and of a size to extend over thebody-openings I6, l1 and which has ears l9 projecting from itsdiametrically opposite sides having sockets therein for registering withdowel pins 20 rising from the top face of the body for properlycentering the This invention relates to certain new and usemlimprovements in a safety cap for tanks or containers used forstoringgasoline and other cover on the latter and preventing relativeturning of such parts. This cover has an annular depending fiange 21having a plurality of radial vent openings 22 therein and its bottomedge rests flatwise on the top side of the cap-body,

as shown in Figure 1, to provide a venting chamber between the body andthe cover. Depending centrally from the cover I8 is a hub or collar 23having a reduced, externally-threaded extension or shank 2ft containingan axial passage 25 whose upper end communicates with a plurality ofintersecting radial passages 26 and whose lower end is adapted to be invalve-controlled communication with the interior of the tank to whichthe cap is applied. In the assembled position of the cap, this extensionprojects through the body-opening l 6 and a split nut 21 applied theretoand abutting the opposing end of the collar l5 serves to securely retainthe cover against the top side of the body I2. Fitted between the collarand flange portions of the cover and the vent openings ll of thecap-body is a fusible disk or washer '28 which fuses and melts inresponse to a predetermined temperature condition within the tank touncover such vent openings and allow the expanding gases to escapethrough the covervents 22.

A valve-like screw plug 29 is fitted in the lower end of thecap-extension 24 and is provided with an axial opening 30 thereinterminating at its upper end in an upwardly-facing valve seat 3!normally engaged by a ball valve 32 and urged against the same by a coilspring 33 fitted in the axial passage 25 of such extension. One or moreventing grooves 34 are formed in the valve seat 3! to permit normalventing of the tank. With expanding pressures generated in the tank, theball valve opens and the tank is promptly vented through the passages 30and 25 and the vent openings 26 and 22.

I claim as my invention:

1. A safety cap for containers, comprising a cap-body adapted forconnection to the container and having an opening centrally thereof andvent openings in its top wall, a vented, chambered cover applied to thetop wall of said body over said vent openings and having a hollowattaching extension depending therefrom through said body-opening forcommunication at its upper end with the chamber of the cover and at itslower end in valved communication with the tank, and a fusible diskinterposed between said body and said cover over the vent openings ofthe former.

2. A safety cap for containers, comprising a cap-body adapted forconnection to the container and having an opening centrally thereof andvent openings in its top wall, a vented, chambered cover applied to thetop wall of said body over said vent openings and having an attachingextension depending therefrom containing an axial passage opening at itslower end into the tank and at its upper end into the chamber of thecover, said passage being provided at its lower end with a valve-seat, aspring-urged valve disposed in said passage and normally engaging itsseat, and a fusible disk interposed between said body and said coverover the vent openings of the former. a

3. A safety cap for containers, comprising a cap-body adapted forconnection tothe container and having a depending collar defining .acentral opening and vent openings in its top wall about the same, acover detachably mounted on the top wall of said body and shaped'toprovide a chamber having vent openings at its periphery,

said cover having a threaded attaching extension depending therefromcontaining an axial passage opening at its lower end into the tank andat its upper end into the chamber of the cover, a nut applied to saidextension for abutting engagement with said body-collar to retain thecover in place, said passage being provided at its lower end with avalve-seat, a spring-urged valve disposed in said passage and normallyengaging its seat, and a fusible disk interposed between said body andsaid cover over the vent openings of the former.

EUGENE W. KNOWLTON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,273,737 Snyder Feb. 17, 1942FOREIGN PATENTS Number Country 7, Date 1,405 Great Britain 1919

